Tracking the market and economic trends that shape your finances.

Here’s a weekly roundup of alleged cons, frauds and schemes to watch out for.

When a stranger calls: The FBI is warning consumers to take caution with telemarketers. When consumers disclose personal or financial information over the telephone, they increase the risk of becoming victims of telemarketing fraud, according to an advisory on the FBI website. Be particularly careful if the caller says any of the following:

“Act now or the offer won’t be good.”

“You’ve won a free gift [vacation or prize]. But you have to pay postage and handling or other charges.”

“You must send money or give a credit card or bank account number.”

“You can’t afford to miss this high-profit, no-risk offer.”

If the caller makes any of those statements, just say, “No thank you,” and hang up the telephone, the FBI suggests.

Bogus domain-name fees: The Federal Trade Commission has closed a fraudulent domain-name-registration business that tricked people into paying fees to maintain their Web addresses. The Toronto-based company, Internet Listing Service, sent phony invoices to customers warning them that their Web addresses would expire if they failed to pay a fee. The company asked for fees to “direct mass traffic” to customer sites – a service that resulted in no additional traffic to payers’ sites, according to the FTC.

Malware attack: The proliferation of nasty online programs called “malware” accelerated during the previous quarter, said computer security firm McAfee – which said it found 10 million new bits of malware during the first half of 2010. “This makes the first six months of 2010 the most active half-year ever for total malware production,” the company said. Among the major threats were so-called “AutoRun” attacks, which spread through portable storage devices and USB drives. Also continuing to cause problems are Facebook-related bugs – often called Koobface – which trick the social network’s users into going to infected websites. Beware of strange Facebook e-mail!

Kids aren’t safe from identity theft: The latest form of identity theft is targeting children. Thieves are targeting children’s Social Security numbers — long before the child has a job or a bank account — and using them to fraudulently obtain credit and run up huge debt they will never pay off, the Associated Press reported. “The back door is wide open. We’re trying to get lenders to understand this,” said Julia Jensen, a Kansas City, Mo., FBI agent who said she discovered the scheme during a mortgage fraud investigation. Experts say the fraud will be difficult to stop because it’s so easily concealed and targets vulnerable and unsuspecting victims. “This is an invisible crime, with invisible victims who don’t have enough support out there to help them,” Linda Foley of the ID Theft Resource Center in San Diego told the Associated Press.